[GHC] #8044: "Inaccessible code" error reported in wrong place

[GHC]

#8044: "Inaccessible code" error reported in wrong place
--------------------------------------------+------------------------------
        Reporter:  goldfire                 |            Owner:
            Type:  bug                      |           Status:  new
        Priority:  normal                   |        Milestone:
       Component:  Compiler (Type checker)  |          Version:  7.7
      Resolution:                           |         Keywords:  GADTs
Operating System:  Unknown/Multiple         |     Architecture:
 Type of failure:  None/Unknown             |  Unknown/Multiple
       Test Case:                           |       Difficulty:  Unknown
        Blocking:                           |       Blocked By:
                                            |  Related Tickets:
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Comment (by heisenbug):

 I doubt the type family is valid

 {{{
 type family Frob a where
   Frob Int = Int
   Frob x   = Char
 }}}

 The second clause should give the same result for `x = Int` than the first
 (namely `Int`), but it results in `Char`. Richard can surely express it
 better than me, though I wonder why it is not rejected at all?

 ''(I sincerely hope I did not mess this up!)''

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8044#comment:2>
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